Tag Archives: CQL

DataStax Java Driver: 2.2.0-rc1 released!

via DataStax Java Driver: 2.2.0-rc1 released! : DataStax.

The Java driver team is pleased to announce the release of version 2.2.0-rc1, which brings parity with Cassandra 2.2. Here’s what the new Cassandra features change for driver users:

Tuning Hadoop & Cassandra : Beware of vNodes, Splits and Pages

via Brian ONeill’s Random Thoughts: Tuning Hadoop & Cassandra : Beware of vNodes, Splits and Pages.

When running Hadoop jobs against Cassandra, you will want to be careful about a few parameters.

Specifically, pay special attention to vNodes, Splits and Page Sizes.

vNodes were introduced in Cassandra 1.2.  vNodes allow a host to have multiple portions of the token range.  This allows for more evenly distributed data, which means nodes can share the burden of a node rebuild (and it doesn’t fall all on one node).  Instead the rebuild is distributed across a number of nodes.  (way cool feature)

BUT, vNodes made Hadoop jobs a little trickier…

The first time I went to run a Hadoop job using CQL, I was running a local Hadoop cluster (only one container) against a Cassandra with lots of vNodes (~250).  I was running a simple job (probably a flavor of word count) over a few thousand records.  I expected the job to complete in seconds.  To my dismay, it was taking *forever*.

DataStax NodeJS Driver for Apache Cassandra

via datastax/nodejs-driver · GitHub.

Node.js driver for Apache Cassandra. This driver works exclusively with the Cassandra Query Language version 3 (CQL3) and Cassandra’s native protocol.